_base.headings.scss

This module defines the font-sizes for your headings. It provides variables for you to override:

$inuit-heading-size-1:  36px !default;
$inuit-heading-size-2:  30px !default;
$inuit-heading-size-3:  24px !default;
$inuit-heading-size-4:  20px !default;
$inuit-heading-size-5:  16px !default;
$inuit-heading-size-6:  14px !default;

Alter these variables to your likes.

Furthermore, it provides abstract classes for each heading-size:

h1,
.alpha {
    ...
}

h2,
.beta {
    ...
}

h3,
.gamma {
    ...
}

h4,
.delta {
    ...
}

h5,
.epsilon {
    ...
}

h6,
.zeta {
    ...
}

Imagine, you've got a heading somewhere on your page with a h1-size, but it must not be an actual h1 (e.g. for SEO reasons). You can then do the following:

<h2 class="alpha">Lorem Ipsum</h2>